Soft gamma rays from low accreting supermassive black holes and connection to energetic neutrinos

Abstract

The Universe is filled with a diffuse background of MeV gamma-rays and PeV neutrinos, whose origins are unknown. Here, we propose a scenario that can account for both backgrounds simultaneously. Low-luminosity active galactic nuclei have hot accretion flows where thermal electrons naturally emit soft gamma rays via Comptonization of their synchrotron photons. Protons there can be accelerated via turbulence or reconnection, producing high-energy neutrinos via hadronic interactions. We demonstrate that our model can reproduce the gamma-ray and neutrino data. Combined with a contribution by hot coronae in luminous active galactic nuclei, these accretion flows can explain the keV -- MeV photon and TeV -- PeV neutrino backgrounds. This scenario can account for the MeV background without non-thermal electrons, suggesting a higher transition energy from the thermal to non-thermal Universe than expected. Our model is consistent with X-ray data of nearby objects, and testable by future MeV gamma-ray and high-energy neutrino detectors.

Published in Nature Communications. Conclusions unchanged. Calculation methods and presentations are improved. Discussions are extended

References in corpus (31)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First M87 Event Horizon Telescope Results. V. Physical Origin of the Asymmetric Ring
• An Observational Determination of the Bolometric Quasar Luminosity Function
• The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV
• Toward the Standard Population Synthesis Model of the X-Ray Background: Evolution of X-Ray Luminosity and Absorption Functions of Active Galactic Nuclei Including Compton-Thick Populations
• The Chandra Deep Field-South Survey: 7 Ms Source Catalogs
• Observation and Characterization of a Cosmic Muon Neutrino Flux from the Northern Hemisphere using six years of IceCube data
• eROSITA Science Book: Mapping the Structure of the Energetic Universe
• Parametrization of gamma-ray production cross-sections for pp interactions in a broad proton energy range from the kinematic threshold to PeV energies
• Constraining High-Energy Cosmic Neutrino Sources: Implications and Prospects
• Cosmic X-ray background and Earth albedo Spectra with Swift/BAT
• The Origin of the Extragalactic Gamma-Ray Background and Implications for Dark-Matter Annihilation
• The extragalactic background light revisited and the cosmic photon-photon opacity
• IceCube-Gen2: A Vision for the Future of Neutrino Astronomy in Antarctica
• The Disc-Jet Symbiosis Emerges: Modeling the Emission of Sagittarius A* with Electron Thermodynamics
• High-Energy Neutrino Emission from Short Gamma-Ray Bursts: Prospects for Coincident Detection with Gravitational Waves
• Time-Dependent Stochastic Particle Acceleration in Astrophysical Plasmas: Exact Solutions Including Momentum-Dependent Escape
• Magnetorotational Turbulence and Dynamo in a Collisionless Plasma
• High Energy Neutrino Flashes from Far-Ultraviolet and X-ray Flares in Gamma-Ray Bursts
• Electron Heating by the Ion Cyclotron Instability in Collisionless Accretion Flows. I. Compression-Driven Instabilities and the Electron Heating Mechanism
• Gamma-Ray and Neutrino Backgrounds as Probes of the High-Energy Universe: Hints of Cascades, General Constraints, and Implications for TeV Searches
• The Cosmic MeV Gamma-ray Background and Hard X-ray Spectra of Active Galactic Nuclei: Implications for the Origin of Hot AGN Coronae
• Angular Momentum Transport and Particle Acceleration during Magnetorotational Instability in a Kinetic Accretion Disk
• Electron Heating by the Ion Cyclotron Instability in Collisionless Accretion Flows. II. Electron Heating Efficiency as a Function of Flow Conditions
• Gamma-ray observations of low-luminosity active galactic nuclei
• The Extragalactic Gamma-Ray Background from Core Dominated Radio Galaxies
• Nuclear activity in nearby galaxies: Mid-infrared imaging with the VLT
• Externally heated protostellar cores in the Ophiuchus star-forming region
• The LOFAR view of NGC 3998, a sputtering AGN
• Cosmic Gamma-ray Background Radiation
• Cosmological Evolution of Flat-Spectrum Radio Quasars based on the {\it Swift}/BAT 105-month Catalog and Their Contribution to the Cosmic MeV Gamma-ray Background Radiation

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• TeV Gamma-Rays from the Low-Luminosity Active Galactic Nucleus NGC 4278: Implications for the Diffuse Neutrino Background
• Physical origin of very-high-energy gamma rays from the low-luminosity active galactic nucleus NGC 4278 and implications for neutrino observations
• Particle Astrophysics with High and Ultrahigh Energy Neutrinos
• Interpreting Swift and NuSTAR Observations of the Low-Luminosity Active Galactic Nucleus NGC 4278 with Radiatively Inefficient Accretion Flows and Implications for Neutrino Emission